I am doing it with the help of nicotine patches and Zyban, an antidepressant marketed as a stop-smoking aid because it decreases compulsive behavior. I told a lot of friends I was doing it, and I asked them for their help, any way they could give it. Some are also stopping, others are giving me encouragement; and all that has been a great deal of help. I pay attention to when I want a smoke most and find other things to distract myself with. And I remind myself that the urge for a smoke passes in about five minutes, and that makes it easier to ride it out.
I didn't plan it this way, but my closest friends who smoke were out of town when I quit, so I won't know how they'll react till Friday when I'll be out with a bunch of smokers, including them. By then it'll be a matter of pride not to smoke, but I think it will be hard to resist all the cues, like drinking around other smokers. We'll see.